CN102597538A - Control arrangement - Google Patents

Control arrangement Download PDF

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Publication number
CN102597538A
CN102597538A CN2010800328266A CN201080032826A CN102597538A CN 102597538 A CN102597538 A CN 102597538A CN 2010800328266 A CN2010800328266 A CN 2010800328266A CN 201080032826 A CN201080032826 A CN 201080032826A CN 102597538 A CN102597538 A CN 102597538A
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CN
China
Prior art keywords
control
actuator
spool
control valve
pressure
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Pending
Application number
CN2010800328266A
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Chinese (zh)
Inventor
C·法格鲁德
J·特雷萨顿
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
EATON Co
Original Assignee
Ultronics Ltd
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Ultronics Ltd filed Critical Ultronics Ltd
Publication of CN102597538A publication Critical patent/CN102597538A/en
Pending legal-status Critical Current

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Classifications

    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
    • F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
    • F15B21/00—Common features of fluid actuator systems; Fluid-pressure actuator systems or details thereof, not covered by any other group of this subclass
    • F15B21/08—Servomotor systems incorporating electrically operated control means
    • F15B21/087—Control strategy, e.g. with block diagram
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
    • F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
    • F15B1/00—Installations or systems with accumulators; Supply reservoir or sump assemblies
    • F15B1/02—Installations or systems with accumulators
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
    • F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
    • F15B11/00—Servomotor systems without provision for follow-up action; Circuits therefor
    • F15B11/02—Systems essentially incorporating special features for controlling the speed or actuating force of an output member
    • F15B11/028—Systems essentially incorporating special features for controlling the speed or actuating force of an output member for controlling the actuating force
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
    • F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
    • F15B11/00—Servomotor systems without provision for follow-up action; Circuits therefor
    • F15B11/02—Systems essentially incorporating special features for controlling the speed or actuating force of an output member
    • F15B11/04—Systems essentially incorporating special features for controlling the speed or actuating force of an output member for controlling the speed
    • F15B11/046—Systems essentially incorporating special features for controlling the speed or actuating force of an output member for controlling the speed depending on the position of the working member
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
    • F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
    • F15B15/00—Fluid-actuated devices for displacing a member from one position to another; Gearing associated therewith
    • F15B15/02—Mechanical layout characterised by the means for converting the movement of the fluid-actuated element into movement of the finally-operated member

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  • Engineering & Computer Science (AREA)
  • Physics & Mathematics (AREA)
  • Fluid Mechanics (AREA)
  • Mechanical Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Chemical & Material Sciences (AREA)
  • Analytical Chemistry (AREA)
  • Fluid-Pressure Circuits (AREA)
  • Multiple-Way Valves (AREA)

Abstract

A control arrangement for use in a hydraulic control system including a control valve of the type having at least two movable elements (16,18), comprises the steps of : controlling the positions of the two movable elements (16,18) such that fluid from a common fluid pressure source is applied to both of the control surfaces of an actuator, the control surfaces being of different effective areas, to drive the actuator for movement.

Description

Controlling schemes
Technical field
The present invention relates to controlling schemes, especially a kind of method that the operation of control valve is controlled, the control valve of said type have two removable or slidably element (below be called the double spool control valve) to allow actuator high-speed motion associated therewith.
Background technique
Hydraulic control system is widely used in the operation of control excavating device, hoist, arm and many like devices.The said control system that is used for wherein generally includes the control valve that is rendered as the spool form that can in the chamber, slide; The determining positions of this spool which the connection relatively high pressure fluid in a pair of discharge valve port on the time of any setting, and which connects low pressure.
Recently, the double spool control valve is applied.Owing to can control the position that is occupied by this double spool independently, this type device occupies some advantages than single spool device.Yet the controlling schemes and those that are generally used for driving this type of control valve are closely similar by the scheme that relates to said single spool device that success is used.
Summary of the invention
The purpose of this invention is to provide the controlling schemes that is used for this type of control valve, allow to utilize said control valve to strengthen the performance of controlled plant.
According to the present invention; It provides a kind of controlling schemes that is used to comprise the hydraulic control system of the control valve with at least two displaceable element types; This controlling schemes may further comprise the steps: the position of controlling said two displaceable elements; Make and two working surfaces that are applied to actuator from the fluid of common fluid pressure source move to drive said actuator, these two control surfaces are formed with the different effective zone.
The advantage of aforesaid operations pattern is, said actuator can be relative to promptly moving when slight loading, and it is relatively low with the clean amount that realizes said mobile fluid to be applied to this actuator, and the fluid that returns of this actuator is got back to said confession stream pipeline certainly.Because net flow body demand is low relatively, it can be met rapidly through the pump of association.
Also proposed to apply therein second operator scheme of different pressures to said actuator, such operator scheme allows on both direction, to drive effectively this actuator, usually with slower speeds.The power that when operating with this pattern, is produced by this actuator is greater than the power that when operating according to first operator scheme, can obtain.
As required, said controlling schemes can be changed between these operator schemes easily.
When operating, will be appreciated that owing to reduced required pump output and can realize the usefulness saving sometimes according to said first operator scheme.Yet usually, it does not reduce pump output, but can realize actuating more at a high speed.In addition, because said Returning fluid only need be back to said control valve rather than be back to for example fluid tank and pump, can reduce the energy loss of said internal system.
Preferably, expression capable of using put on said actuator the said control valve of data manipulation of position of displaceable element of pressure and/or this control valve to allow implementing control with the mode of closed loop.
Description of drawings
With reference to accompanying drawing, further describe the present invention through instance, wherein:
Fig. 1 is the schematic representation that comprises the control system of double spool control valve; And
Fig. 2 shows the schematic representation of the said system in the use.
Embodiment
Referring to Fig. 1, be shown schematically in the double spool control valve of the operation of the control system that is used to the equipment of controlling, said equipment is such as there being excavator, crane, it is hydraulic control that hoist, or similar devices, these equipment have partial function at least.Said control valve comprises main valve body 10, wherein is formed with valve pocket 12,14.Be provided with corresponding spool 16,18 (forming the said double spool of said control valve) in each valve pocket 12,14.During use, being connected on the main valve body 10 is confession stream and the return pressure pipeline that connects with corresponding valve port 20,22 respectively, and this valve port is through supplying stream and return pressure pipeline 24,26 communicated cavitys 12,14.Chamber 12; In 14 each further comprises or has and its associated control valve port 28; Should understand the determining positions of each spool 16,18 within corresponding chamber 12,14 each control valve port 28 whether with related confession stream valve port 20 or related backflow valve port 22 be communicated with.According to the said position shown in Fig. 1, can close and supply stream valve port 20 if the spool in left side 16 moves to position then this spool 16 of rising, allow between control valve port 28 and the backflow valve port 22 to be communicated with not limited mode relatively.On the contrary, reduce the right side spool and cause that backflow valve port 22 closed by spool 18, allow to be communicated with between control valve port 28 and the backflow valve port 22.Will be appreciated that spool 16,18 moves in the opposite direction will put upside down described connection.
If main valve body 10 is installed in such as on the hoist, can be used to control the position of the lift arm of this hoist with the pilot line that is connected of control valve port 28 30 interior pressure.For example; Spool 16; 18 can cause that to moving of position as previously mentioned said arm rises; Be provided for an end of the piston of the said position that is used to control said arm because be in the fluid that supplies under the flowing pressure condition through chamber 14, the fluid that flows out from said piston the other end can return through another chamber 12.Spool 16 move downward and spool 18 move upward can the said piston of conversion connection, cause said arm to reduce.
By 32 controls of pilot valve piece, these pilot valve piece 32 controls are applied to the fluid volumes of the other end of spool 16,18, just control its pressure by spool 16,18 position occupied.Pilot valve piece 32 comprises pair of control spool 34; The electric current that its position is applied on the coil that is carried by each control spool 34 through control is realized Electromagnetic Control; The magnetic field that causes thus with interact between the related permanent magnet 36, move to needed position thereby drive each control spool 34.Control unit 40 can be used for controlling the electric current that is applied on each coil, and controls each control spool 34 position occupied thus.
Each control guiding valve 34 comprises one group of annular shoulder, and it is used to control the valve port that is connected with return pressure, the connection between the middle chamber of handling pressure and locating in each end of each spool 16,18.
From shown position, mobile spool 16 upper end portions, left side that cause of control spool 34 to the leftward position in left side are applied in return pressure, and its underpart is applied in manipulation pressure, and consequently spool 16 is in its raised position.If control spool 34 moves right with reference to the orientation shown in the figure, the said underpart of spool 16 can receive return pressure so, and said upper end portion will receive manipulation pressure simultaneously, cause that spool 16 moves downward.Realize the control of position that occupies by right side spool 18 in a similar manner.Should be appreciated that and to control spool 34 residing positions independently.Therefore, the position that occupies of spool 16,18 can be controlled equally independently of one another.
Each pilot line 30 is connected with pressure transducer 38, and in use, this pressure transducer acts on the signal of the pressure of piston to corresponding control unit 40 feedback expressions.In addition, position transducer is monitored the position of each spool 16,18 expediently, and the output result of position transducer offers control unit 40, thereby realizes the closed loop control for spool 16,18.In use, the operator uses the for example control executing mechanism of controlling rod form, and to control unit 40 control signal to be provided, this control signal shows that for example said arm moves needed direction and speed, perhaps other parameters that are controlled.For example, if he hopes to rise said arm, he can draw said controlling rod, pushes away this bar and reduces to indicate said arm.Therefore can know; If sensing the operator, control unit 40 draw operating handle indication arm to raise; This control unit can carry electric current to move to shown position to impel control spool 34 to coil; Thereby spool 16,18 is moved to shown position, and then apply the pressure regulated toward the direction that arm is raise to piston.On the contrary, if said controlling rod is pushed to indicate said arm to reduce, the position that control spool 34 occupies is switched, and drives spool 16 from other direction, thereby 18 reduce arm.
In preceding text of the present invention, the extreme position of spool 16,18 has been described, just make the confession stream valve port of each valve pocket 12,14 or the position of backflow valve port 20,22 complete openings.But, should be realized that spool 16,18 can be driven to the neutral position usually.In addition, because spool 16,18th is independent of each other, its position that occupies separately also can be controlled independently of each other, so the series of operation scheme can be arranged.For example, if the operator through big relatively angular movement controlling rod, just can be pushed into corresponding extreme position to spool 16,18, make arm produce motion relatively at a high speed.If operating handle to stir angle less, control unit 40 opening degree that can reduce the valve port 22 that for example refluxes accordingly moves with the speed that reduces to cause said arm so.
As shown in Figure 2, said control valve is used to control the stretching, extension and the retraction of actuator 50, and this actuator is included in the cylinder body 52 that there is piston mobile 54 its inside.Piston 54 and cylinder body 52 limit first Room that is connected with control valve port 28 through one of pilot line 30 jointly, and this control valve port is related with chamber 12 and spool 16.Piston 54 and cylinder body 52 further limit second Room that is connected with control valve port 28 through another pilot line 30, and this control valve port is related with chamber 14 and spool 18.
Take-off lever 60 is connected with piston 54, and this piston is through second Room 58 and stretch out cylinder body 52.The effective area that the existence that will be appreciated that said take-off lever 60 has caused piston 54 to be exposed to the inner hydrodynamic pressure in second Room 58 is significantly less than it and is exposed to the effective area at the inner hydrodynamic pressure in first Room 56.Therefore; If as taking place in first operator scheme of said controlling schemes to chamber 56; 58 all apply the fluid that comes from the uniform pressure source, promote this piston 54 thereby the said effective area difference under this fluid pressure action can cause applying power to piston 54 to the right by orientation as shown in the figure.As long as applied force is enough big to overcome the load that any outside applies, just will produce the motion of piston 54.If as taking place in second operator scheme, apply different pressure, then in the chamber 56,58 which depended on of the extension of said actuator or retraction has the higher pressure fluid that applies on it.
As mentioned above, the control of said control valve is applied to control valve port 28 and thereby is applied to the pressure of chamber 56,58.When this control valve operates according to second operator scheme, can apply high flowing pressure to the second chamber 58 that supplies, first Room 56 is connected to lower return pressure simultaneously.The result; Piston 54 moves to the left side in orientation shown in figure; The fluid that flows out from said confession stream pipeline flow to second Room 58 through supplying stream valve port 20 and control valve, and the fluid that flows out from first Room 56 is flowed through said control valve to refluxing valve port 22 and flow to fluid tank therefrom.Change said control valve spool 16,18 the position with driven plunger 54 to as figure shown in the right side in orientation.
According to the present invention; Under the certain operations condition; Through controlling said control valve according to regeneration steer mode (referring to said first operator scheme here), can obtain more operation at a high speed, in this pattern its be not depend on said with chamber 56; 58 differential pressures that are connected on the different pressure source meanings remove to drive said actuator, but have utilized the difference area.In this operator scheme,, apply and supply on flowing pressure to two chambers 56,58 of said actuator as shown in Figure 2 when needs orientation to the right during mobile piston 54 shown in figure.Because the effective area that is under pressure of said piston 54 there are differences; Apply hydrodynamic pressure to two chamber 56 from common pressure source; 58 will cause moving of needed said actuator, as long as the power that is produced by the pressure that is applied to said different area can overcome the load that any outside applies.The mobile fluid that causes of piston 54 is discharged from second Room 58.This fluid is not to flow back into said case, but flows into the output of said confession stream pipeline with make-up pump, thereby allows to drive this pump with the flow output that reduces.Perhaps, said pump output is not the flow output function to reduce, but it can remain on higher level, and can be used for realizing the increase of said actuator percentage of elongation through the regenerant flow that invention obtains.
Because this operator scheme can only be used for driving in one direction said actuator; Only if be to be understood that to apply suitable external loading driving this actuator in the opposite direction, said operator scheme needs change back said second pattern with in the opposite direction mobile of realization actuator.
Closed loop control like the said control valve of preceding description has utilized valve element position and pressure information, makes this system efficiently to move and guarantees to obtain required motion speed simultaneously.Further, through utilizing the minimizing of the fluid flow path length that the single system structure can realize, caused the minimizing of energy loss.
The volume that during such recovery stream, flows back into the said fluid of said confession stream pipeline is easy to confirm, said control unit can utilize operation that the said volume calculation that so flows back to controls said pump with optimization system usefulness.
As previously mentioned, except the mentioned said spool of this paper, said control valve can have movably other forms of or part slidably, and the present invention can be equally applicable to this type valve.
The regenerative operation of typical single spool control valve is known, flows to realize regeneration but need the additional assemblies of valve or pipe-line system form be increased to control system usually.For example; The regenerative operation that comprises the system of typical single spool control valve can be realized through pilot valve control check valve is provided; This check valve can be opened allowing flowing to opposite side from the fluid of said piston one side when regeneration move to take place, or through for example providing solenoid operated valve to carry out this function and to allow user's control operation of whether regenerating.Other scheme requires an end of said piston to connect high pressure all the time, though not like this in use the time yet, but like this and bad, and be not suitable use in some applications.
Comparatively speaking, said scheme of the present invention just can realize regeneration through the method for operation of suitably controlling said control valve simply, does not require extra valve and pipeline or analog.Therefore, can realize regeneration simply, easily, can not cause a large amount of fringe costs, also not require extra part and the maintenance that relates to thus etc.
Preceding method can carry out many changes and distortion and not exceed protection scope of the present invention.

Claims (5)

1. controlling schemes that is used to comprise the hydraulic control system of control valve; The control valve of said type has at least two displaceable elements; Said scheme may further comprise the steps: the position of said at least two displaceable elements of control makes fluid from common fluid pressure source be applied to two working surfaces with different effective zone of actuator and drives said actuator and move.
2. scheme according to claim 1 is characterized in that it is switchable to second operator scheme, and the pressure that in this pattern, is applied to said actuator is different.
3. scheme according to claim 1 and 2 is characterized in that expression capable of using puts on this control valve of data manipulation of position of said displaceable element of pressure and/or the said control valve of said actuator, to allow the control of closed-loop fashion.
4. according to the described scheme of above-mentioned arbitrary claim, it is characterized in that also comprising pump, the operation flow of this pump is controlled according to said operator scheme.
5. hydraulic control system; It comprises the control valve with at least two displaceable elements and controls this displaceable element control of position unit; The position of said at least two displaceable elements of said control unit control; Make fluid from common fluid pressure source be applied to two of actuator and be formed with on the working surface in different effective zone, move to drive said actuator.
CN2010800328266A 2009-07-20 2010-07-02 Control arrangement Pending CN102597538A (en)

Applications Claiming Priority (3)

Application Number Priority Date Filing Date Title
GB0912549.3 2009-07-20
GB0912549A GB2472004A (en) 2009-07-20 2009-07-20 Control arrangement for controlling movement of a differential piston in a hydraulic circuit
PCT/EP2010/059476 WO2011009705A1 (en) 2009-07-20 2010-07-02 Control arrangement

Publications (1)

Publication Number Publication Date
CN102597538A true CN102597538A (en) 2012-07-18

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CN2010800328266A Pending CN102597538A (en) 2009-07-20 2010-07-02 Control arrangement

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US (1) US20120279212A1 (en)
EP (1) EP2456987A1 (en)
CN (1) CN102597538A (en)
GB (1) GB2472004A (en)
WO (1) WO2011009705A1 (en)

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Publication number Priority date Publication date Assignee Title
GB2472005A (en) * 2009-07-20 2011-01-26 Ultronics Ltd Control arrangement for monitoring a hydraulic system and altering opening of spool valve in response to operating parameters
US20130305916A1 (en) * 2012-05-17 2013-11-21 PHD. Inc. Pneumatic cylinder with pressure moderator
EP3138163B1 (en) 2014-04-30 2020-11-04 Eaton Intelligent Power Limited High pressure sealed electrical connector
CN106523480B (en) * 2016-11-23 2018-03-09 南京航空航天大学 A kind of hydraulic servo driving system and control method
DE102018115701A1 (en) * 2018-04-30 2019-10-31 Tries Gmbh & Co. Kg Valve unit with two pilot valves and two main valves
DE102018217337A1 (en) * 2018-10-10 2020-04-16 Festo Se & Co. Kg Movement device, tire handling device and method for operating a fluidic actuator

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JP2001011899A (en) * 1999-06-28 2001-01-16 Kobe Steel Ltd Hydraulic circuit for work machine and hybrid work machine
US20030106420A1 (en) * 2001-12-10 2003-06-12 Kazunori Yoshino Hydraulic control system with regeneration
WO2009000472A1 (en) * 2007-06-26 2008-12-31 Robert Bosch Gmbh Method and hydraulic control arrangement for supplying a pressure medium to at least one hydraulic consumer
US7518523B2 (en) * 2007-01-05 2009-04-14 Eaton Corporation System and method for controlling actuator position

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Publication number Priority date Publication date Assignee Title
US4416187A (en) * 1981-02-10 1983-11-22 Nystroem Per H G On-off valve fluid governed servosystem
JP2001012406A (en) * 1999-06-28 2001-01-16 Kobe Steel Ltd Hydraulic circuit for working machine and hybrid working machine
JP2001011899A (en) * 1999-06-28 2001-01-16 Kobe Steel Ltd Hydraulic circuit for work machine and hybrid work machine
US20030106420A1 (en) * 2001-12-10 2003-06-12 Kazunori Yoshino Hydraulic control system with regeneration
US7518523B2 (en) * 2007-01-05 2009-04-14 Eaton Corporation System and method for controlling actuator position
WO2009000472A1 (en) * 2007-06-26 2008-12-31 Robert Bosch Gmbh Method and hydraulic control arrangement for supplying a pressure medium to at least one hydraulic consumer

Also Published As

Publication number Publication date
GB2472004A (en) 2011-01-26
US20120279212A1 (en) 2012-11-08
GB0912549D0 (en) 2009-08-26
EP2456987A1 (en) 2012-05-30
WO2011009705A1 (en) 2011-01-27

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Application publication date: 20120718